1. Field of the Invention
The present invention relates to a wireless IC device, and more specifically to a wireless IC device such as a non-contact wireless IC tag used in a RF-ID (Radio Frequency Identification) system, for example.
2. Description of the Related Art
In the related art, there have been proposed wireless IC devices including a wireless IC chip and a radiation plate.
For example, in a non-contact wireless IC tag 100 disclosed in Japanese Unexamined Patent Application Publication No. 2004-280390, as shown in FIG. 7A showing its internal configuration, and FIG. 7B that is a cross-sectional view taken along the portion A-A′ of FIG. 7A, a loop antenna 112 is formed as a radiation plate on one principal surface of a resin sheet 115 serving as a substrate, connection terminals 114 are provided at the open end of the loop antenna 112, and a wireless IC chip 111 is mounted on the connection terminals 114 and covered with a surface sheet 120 via an adhesive layer 150 (see, for example, Japanese Unexamined Patent Application Publication No. 2004-280390).
However, in cases where, as in this wireless IC device, the wireless IC chip and the radiation plate need to be connected so as to be electrically continuous with each other, it is necessary to mount the wireless IC chip on the connection terminals with high precision. Thus, high-precision mounting equipment becomes necessary, leading to an increase in manufacturing cost.
In addition, if there is a large displacement of the mounting position of the wireless IC chip with respect to the connection terminals, electrical connection is not established between the wireless IC chip and the radiation plate, so the wireless IC device ceases to function.
Further, in cases where a specification such as communication range varies, if elements having a varying antenna pattern, circuit configuration, and the like are used in accordance with the specification, the manufacturing cost increases.